Source : Webster's Revised Unabridged Dictionary (1913)

Basil \Bas"il\, n. [F. basilic, fr. L. badilicus royal, Gr. ?,
   fr. ? king.] (Bot.)
   The name given to several aromatic herbs of the Mint family,
   but chiefly to the common or sweet basil ({Ocymum
   basilicum}), and the bush basil, or lesser basil ({O.
   minimum}), the leaves of which are used in cookery. The name
   is also given to several kinds of mountain mint
   ({Pycnanthemum}).

   {Basil thyme}, a name given to the fragrant herbs {Calamintha
      Acinos} and {C. Nepeta}.

   {Wild basil}, a plant ({Calamintha clinopodium}) of the Mint
      family.

Source : WordNet®

basil thyme
     n : fragrant European mint having clusters of small
         violet-and-white flowers; naturalized especially in
         eastern North America [syn: {basil balm}, {mother of
         thyme}, {Acinos arvensis}, {Satureja acinos}]